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21.
Macrothrix mexicanus sp. nov. is described from central México, a transition zone between the nearctic and neotropics. All localities where it was found are over 1800 meters above sea level. It shows many resemblances with M. laticornis, M. camjatae and M. rosea but is characterized by a persistent dorsal tooth on the valve keel, a spinous papilla on the basipodite of the antenna, the second thoracic limb with a long conical sensillum between scraper 1 and the gnathobase, the endopod of trunk limb IV having two setae; the postabdomen with the dorsal margin bilobed, and the distal segment of the seta natatoria which is unusually long.Abbreviations used on figures EN
Endopodite
- EP
Epipodite
- EX
Exopodite
- IDL
Inner distal lobe
- ODL
Outer distal lobe
- GT
Gnatobase
- E1
Endite 1
- E2
Endite 2
- E3
Endite 3 相似文献
22.
Insertional mutagenesis and recovery of interrupted genes of Streptococcus mutans by using transposon Tn917: preliminary characterization of mutants displaying acid sensitivity and nutritional requirements. 总被引:6,自引:2,他引:4
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J A Gutierrez P J Crowley D P Brown J D Hillman P Youngman A S Bleiweis 《Journal of bacteriology》1996,178(14):4166-4175
New vectors were constructed for efficient transposon Tn917-mediated mutagenesis of poorly transformable strains of Streptococcus mutans(pTV1-OK) and subsequent recovery of interrupted genes in Escherichia coli (pT21delta2TetM). In this report, we demonstrate the utility of Tn917 mutagenesis of a poorly transformable strain of S. mutans (JH1005) by showing (i) the conditional replication of pTV1-OK, a repA(Ts) derivative of the broad-host-range plasmid pWVO1 harboring Tn9l7, in JH1005 at the permissive temperature (30 degrees C) versus that at the nonpermissive temperature (45 degrees C); (ii) transposition frequencies similar to those reported for Bacillus subtilis (10(-5) to 10(-4)) with efficient plasmid curing in 90 to 97% of the erythromycin-resistant survivors following a temperature shift to 42 to 45 degrees C; and (iii) the apparent randomness of Tn917 insertion as determined by Southern hybridization analysis and the ability to isolate nutritional mutants, mutants in acid tolerance, and mutants in bacteriocin production, at frequencies ranging from 0.1 to 0.7%. Recovery of transposon-interrupted genes was achieved by two methods: (i) marker rescue in E. coli with the recovery vector pTV21delta2TetM, a tetracycline-resistant and ampicillin-sensitive Tn9l7-pBR322 hybrid, and (ii) "shotgun" cloning of genomic libraries of Tn917 mutants into pUC19. Sequence analyses revealed insertions at five different genetic loci in sequences displaying homologies to Clostridium spp.fhs (66% identity), E. coli dfp (43% identity), and B. subtilis ylxM-ffh (58% identity), icd (citC [69% identity]), and argD (61% identity). Insertions in icd and argD caused nutritional requirements; the one in ylxM-ffh caused acid sensitivity, while those in fhs and dfp caused both acid sensitivity and nutritional requirements. This paper describes the construction of pTV1-OK and demonstrates that it can be efficiently employed to deliver Tn917 into S. mutans for genetic analyses with some degree of randomness and that insertions in the chromosome can be easily recovered for subsequent characterization. This represents the first published report of successful Tn9l7 mutagenesis in the genus Streptococcus. 相似文献
23.
J. F. Romero Collazos M. D. Marrodán E. Gutierrez Redomero 《International Journal of Anthropology》1996,11(1):11-19
Anthropometric characteristics of proportionality, body composition and somatotype have been determined in a group of 72 Spanish
judoists. The sample includes the junior male and female National Team, and seniors competitors in the last Olimpic Games
held in 1992, and participants in the National Championship of 1993. The methodology has been used according to Weiner and
Lourie(1981)and MOGAP procedures described by Borms et al. (1979). The obtained results show a similar proportionality profile
and mesoendomorphic mean somatotype in both male and female series. However, were found significant differences between sexes
as well as depending of weight categories. 相似文献
24.
Germ-Line Mutations in the von Hippel–Lindau Tumor-Suppressor Gene Are Similar to Somatic von Hippel–Lindau Aberrations in Sporadic Renal Cell Carcinoma
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Jean M. Whaley Joseph Naglich Lawrence Gelbert Y. Edward Hsia James M. Lamiell Jane S. Green Debra Collins Hartmut P. H. Neumann Jana Laidlaw Fred P. Li Andres J. P. Klein-Szanto Bernd R. Seizinger Nikolai Kley 《American journal of human genetics》1994,55(6):1092-1102
von Hippel–Lindau (VHL) disease is a hereditary tumor syndrome predisposing to multifocal bilateral renal cell carcinomas (RCCs), pheochromocytomas, and pancreatic tumors, as well as angiomas and hemangioblastomas of the CNS. A candidate gene for VHL was recently identified, which led to the isolation of a partial cDNA clone with extended open reading frame, without significant homology to known genes or obvious functional motifs, except for an acidic pentamer repeat domain. To further characterize the functional domains of the VHL gene and assess its involvement in hereditary and nonhereditary tumors, we performed mutation analyses and studied its expression in normal and tumor tissue. We identified germ-line mutations in 39% of VHL disease families. Moreover, 33% of sporadic RCCs and all (6/6) sporadic RCC cell lines analyzed showed mutations within the VHL gene. Both germ-line and somatic mutations included deletions, insertions, splice-site mutations, and missense and nonsense mutations, all of which clustered at the 3' end of the corresponding partial VHL cDNA open reading frame, including an alternatively spliced exon 123 nt in length, suggesting functionally important domains encoded by the VHL gene in this region. Over 180 sporadic tumors of other types have shown no detectable base changes within the presumed coding sequence of the VHL gene to date. We conclude that the gene causing VHL has an important and specific role in the etiology of sporadic RCCs, acts as a recessive tumor-suppressor gene, and appears to encode important functional domains within the 3' end of the known open reading frame. 相似文献
25.
Abstract: The pentameric subunit composition of a large population (36%) of the cerebellar granule cell GABAA receptors that show diazepam (or clonazepam)-insensitive [3 H]Ro 15-4513 binding has been determined by immunoprecipitation with subunit-specific antibodies. These receptors have α6 , α1 , γ2S , γ2L , and β2 or β3 subunits colocalizing in the same receptor complex. 相似文献
26.
The Eip28/29 gene of Drosophila is an example of a tissue- and stage-specific ecdysone-responsive gene. Its diverse patterns of expression during the third larval instar and a synopsis of those patterns in terms of expression groups have been reported previously. Here we have studied the expression (in transgenic flies) of reporter genes controlled by Eip28/29-derived flanking DNA. During the middle and late third instar, most tissues exhibit normal expression patterns when controlled by one of two classes of regulatory sequences. Class A sequences include only 657 Np of 5′ flanking DNA from Eip28/29. Class B sequences include an extended 3′ flanking region and a minimal (≤93 Np) 5′ flanking region. The class B sequences include all those elements known to be important for ecdvsone induction in cultured cells. They are sufficient to direct the normal premetamorphic induction of Eip28/29 in the lymph glands, hemocytes, proventriculus, and Malpighian tubules. This is consistent with our suggestion that Kc cells are derived from embryonic hematopoietic cells. It is remarkable that the epidermis requires only class A sequences. These are sufficient to up-regulate expression at medinstar and to down-regulate expression at metamorphosis. It follows that the epidermis uses EcREs distinct from those that function in Kc cells. It is possible that the Upstream EcRE, which is nearly silent in Kc cells, is active in the epidermis. © 1994 Wiley-Liss, Inc. 相似文献
27.
C. Gutierrez G. Garcia-Casado R. Snchez-Monge L. Gomez P. Castaera G. Salcedo 《Entomologia Experimentalis et Applicata》1993,66(1):47-52
Crude α-amylase preparations from seven Lepidoptera pests were susceptible to inhibition by salt-soluble proteins of bread
wheat (Triticum aestivum L.) endosperm. Protein fractions that corresponded to tetrameric, dimeric, and monomeric wheat α-amylase inhibitors, were
decreasingly effective against the insect α-amylase activity. To further confirm these results, purified inhibitors were tested
against an α-amylase preparation fromEphestia kuehniella (Zeller). This preparation showed decreased activity when increasing amounts of an heterotetrameric inhibitor (reconstituted
from its isolated subunits WTAI-CM2, -CM3 and -CM16) were assayed. Activity was only partially inhibited by homodimeric (WDAI-1,
synonym 0.53; WDAI-2, synonym 0.19) and monomeric (WMAI-1, synonym 0.28) inhibitors. 相似文献
28.
J. A. Reig S. Viniegra J. J. Ballesta M. Palmero L. M. Gutierrez 《Neurochemical research》1993,18(3):317-323
The role of protein phosphorylation in catecholamine secretion from bovine adrenomedullary chromaffin cells was studied using different protein kinase inhibitors. Naphthalenesulfonamide derivatives as ML9 and ML7, more specific for the myosin light chain kinase, and the calmodulin antagonist W7 inhibited catecholamine secretion 20 and 40% respectively in digitonin-permeabilized chromaffin cells. ML9 also decreased calcium evoked protein phosphorylation of different proteins including tyrosine hydroxylase in permeabilized cells. These naphthalenesulfonamide derivatives showed also an effect in intact cells, ML9 and W7 produced 50% inhibition in catecholamine secretion and45Ca2+ uptake, however H8 had no effect. The partial [3H]nitrendipine binding displacement of these drugs to adrenomedullary membranes suggests that these sulfonamide derivatives could interact directly with L-type calcium channels in intact cells. The results obtained in permeabilized cells suggest a possible role of protein phosphorylation in the regulation of catecholamine secretion in chromaffin cells.The abbreviations used are ML9
1-(5-Chloronaphthalene-1-sulfonyl)1H-hexahydro-1,4-diazepine hydrochloride
- ML7
1-(5-Iodonaphthalene-1-sulfonyl)-1H-hexahydro-1,4 diazepine hydrochloride
- H7
1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride
- H8
N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride
- W7
N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride
- PKI
protein kinase A inhibitor
- HEPES
N-(2-hydroxyethylpiperazine-N-(2 ethanesulfonic acid)
- PIPES
piperazine-N, N-bis (2-ethanesulfonic acid)
- EGTA
[ethylene-bis (oxyethylenenitrilo)] tetraacetic acid
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide gel electrophoresis
- DMEM
Dulbecco's Modified Eagle's medium
- MLC
myosin light chain
- MLCK
myosin light chain kinase
- TH
tyrosine hydroxylase 相似文献
29.
The pea aphidAcyrthosiphon pisum (Harris) and the blue alfalfa aphidA. kondoi Shinji are pests of alfalfaMedicago sativa L. worldwide. The parasitoidAphidium ervi Haliday attacks both species andA. smithi is host specific to pea aphid Experiments were conducted to determine the preference ofA. ervi forA. pisum andA. kondoi at three densities of hosts using the percentages of parasitism and superparasitism, and the distribution of eggs among hosts as criteria. Also examined was the outcome of competition between the two parasitoids when exposed to the same hosts. A. ervi attacks moreA. pisum when provided alone (no choice test) and when provided together in equal numbers withA. kondoi (choice test). There was no significant difference in the number of progeny produced by either parasitoid when a female of each species was introduced simultaneously into the same test unit containingA. pisum hosts. The effects of the pathogenPandora neoaphidis on this competition is reviewed. 相似文献
30.
Roberto de la Herrán Miguel Hermida Juan Andres Rubiolo Jèssica Gómez-Garrido Fernando Cruz Francisca Robles Rafael Navajas-Pérez Andres Blanco Paula Rodriguez Villamayor Dorinda Torres Pablo Sánchez-Quinteiro Daniel Ramirez Maria Esther Rodríguez Alberto Arias-Pérez Ismael Cross Neil Duncan Teresa Martínez-Peña Ana Riaza Adrian Millán M. Cristina De Rosa Davide Pirolli Marta Gut Carmen Bouza Diego Robledo Laureana Rebordinos Tyler Alioto Carmelo Ruíz-Rejón Paulino Martínez 《Molecular ecology resources》2023,23(4):886-904
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. 相似文献